Got in the truck, started fine, drove it up the ramps changed oil and filter. Oil levels fine, yes I did put the plug back in the oil pan, yes I have gas, gauge reads 3/4 tank went to start it to back down the ramps would not start at that time. I can put a little gas in the carburetor; the engine starts up burns out the gas and quits.
Then it sounds like you need to check for fuel pump operation and fuel pressure. Turn the key to start, but not all the way until it turns over. Listen for a hum (2-3 seconds). If you have an assistant & aren’t sure, pull the gas cap & listen from there as someone else turns the key. If there is no hum of the fuel pump start checking fuse/relay/fuel lines/pump connections and such.
It is probable that this has occurred purely by coincidence and has nothing to do with the oil change - unless you were messing with other things and inadvertently disturbed something.
All of that is assuming that you know for sure that your fuel gauge works properly.
Okay, no hum, no vibration nor any indication there is a running pump.
You need to start figuring that out then. I can’t give you the specific low down on how to go about it, but you can go to Autozone’s web page ( http://www.autozone.com ) and if you register you can get online repair info that will likely include some of the basics for checking out the fuel system.
Obvious place to start is w/ fuse / relay - probably in a black box under the hood. But if those are bad you likely have some checking to do as to why.
We have found the relay box when we opened it up, we’re checking into that now.
Fuel pump relay seems to be working, checking autozone. Much thanks